Cleanest

The United States boast some of the world's cleanest food.

It's one of the cleanest cities in the world.

Layla was the cleanest girl walking.

Algiers should become one of the cleanest cities in Algeria.

Setif is one of the cleanest cities in Algeria.

Setif is one of Algeria's cleanest cities.

Algiers needs to be one of the cleanest cities in Africa.

This is the cleanest I've ever seen this room.

The city of Honolulu in Hawaii, and Santa Fe in New Mexico, topped the list of cities with the cleanest air.

Chief executive Andrew Haines said: "Rail is already the cleanest and greenest mode of transporting large numbers of people and goods, but we're committed to cutting our carbon footprint even further. [...]."